Although concrete is one of the most durable, effective and long-lasting building materials known to man, it too has archenemies, namely water-soluble salts and gases. Water, which is an integral ingredient in making concrete, can also be extremely destructive in a few different ways. Concrete damage nearly always involves moisture, and water can carry detrimental substances such as chlorides from road salts into the concrete causing structures to weaken and break down. This article will discuss numerous ways in preventing cracks in concrete.
Water and the substances it introduces into concrete can cause issues such as:
- Organic growth including moss, mold, algae and lichen
- Steel corrosion from chloride
- Freeze/thaw damage
Another major issue that concrete faces is cracks. Concrete is designed for compressive strength and has lower tensile strength. If the internal tensile stresses are greater than the tensile strength of the concrete, cracks can develop. A whole host of influences can contribute to concrete cracking including:
- Drying and/or freeze/thaw shrinkage
- Excess water in the concrete mix.
- Improper or poor preparation of the base or sub-grade
- Lack of or improper curing
Since concrete is known to sometimes crack randomly, contractors attempt to control that by incorporating contraction joints. Contraction joints can be formed with plastic or hardboard preformed strips, saw cuts or tooled in and are easy to maintain and less objectionable than a crack. Construction joints need to be ¼ the thickness of the slab, as the purpose is to create a plane of weakness—basically dictating where the concrete will crack. Concrete should be jointed as soon as possible after installation.
Another way to protect concrete and hopefully prevent cracking is by using a high quality water repellent sealer. Siloxa-Tek 8500 can be used to treat concrete installations that will be exposed to extreme salt and chloride in areas with harsh winter climates prone to freezing, thawing, and salt use on roadways. Additionally, this sealer will help to protect concrete from other aforementioned potential damage including organic growth, chemical corrosion, dirt, staining, efflorescence, and cracking. Preventing Cracks In Concrete is now easy with the help of Redi Mix Colors.